1. Field of the Invention
The present invention is concerned with an arrangement in a roll wrapping apparatus for the application of headers, in particular of soft inner headers or equivalent, to the ends of paper rolls or corresponding rolls.
2. Description of the Prior Art
As a rule, such an arrangement includes a storage unit, in which there are storage members for different sizes of headers.
The arrangement further includes an application unit, which comprises grasping members for holding the header and setting members for transferring the header onto the end of the roll.
Each header is transferred from the storage unit to the application unit by means of a transfer unit in which there are also grasping members for holding the header and, moreover, transfer members for transferring the header from the storage unit to the grasping members of the transfer unit.
By means of the prior-art technique, it has been possible to automatize the transfer of rigid headers from the storage unit onto the roll end quite efficiently (cf., e.g., Finnish Patent No. 56,803). Such a rigid header can be shifted easily, e.g., by means of suction means (suction heads), because, owing to its rigidity, the header retains its shape even if it must be turned and shifted in different directions during the transfer.
It is evident that a soft header, e.g., an inner header of cardboard, cannot be transferred by means of the technique described above, because, during the transfer, the header would tend to be bent and folded, so that its application to the roll end would be impossible. This is the case in particular if, during the transfer, the header is grasped only by one point of limited area.